Decadal climate variability over the North Pacific and North America: Dynamics and predictability
The dynamics and predictability of decadal climate variability over the North Pacific and North America are investigated by analyzing various observational datasets and the output of a state of the art coupled ocean-atmosphere general circulation model that was integrated for 125 years. Both the obs...
Main Authors: | , |
---|---|
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
1996
|
Subjects: | |
Online Access: | http://hdl.handle.net/21.11116/0000-0003-2919-4 http://hdl.handle.net/21.11116/0000-0003-291B-2 http://hdl.handle.net/21.11116/0000-0003-291C-1 |
id |
ftpubman:oai:pure.mpg.de:item_3032643 |
---|---|
record_format |
openpolar |
spelling |
ftpubman:oai:pure.mpg.de:item_3032643 2023-08-20T03:59:25+02:00 Decadal climate variability over the North Pacific and North America: Dynamics and predictability Latif, M. Barnett, T. 1996 application/pdf http://hdl.handle.net/21.11116/0000-0003-2919-4 http://hdl.handle.net/21.11116/0000-0003-291B-2 http://hdl.handle.net/21.11116/0000-0003-291C-1 eng eng info:eu-repo/semantics/altIdentifier/doi/10.1175/1520-0442(1996)009<2407:DCVOTN>2.0.CO;2 http://hdl.handle.net/21.11116/0000-0003-2919-4 http://hdl.handle.net/21.11116/0000-0003-291B-2 http://hdl.handle.net/21.11116/0000-0003-291C-1 Journal of Climate Report / Max-Planck-Institut für Meteorologie info:eu-repo/semantics/article 1996 ftpubman https://doi.org/10.1175/1520-0442(1996)009<2407:DCVOTN>2.0.CO;2 2023-08-01T23:50:16Z The dynamics and predictability of decadal climate variability over the North Pacific and North America are investigated by analyzing various observational datasets and the output of a state of the art coupled ocean-atmosphere general circulation model that was integrated for 125 years. Both the observations and model results support the picture that the decadal variability in the region of interest is based on a cycle involving unstable ocean-atmosphere interactions over the North Pacific. The period of this cycle is of the order of a few decades. The cycle involves the two major circulation regimes in the North Pacific climate system, the subtropical ocean gyre, and the Aleutian low. When, for instance, the subtropical ocean gyre is anomalously strong, more warm tropical waters are transported poleward by the Kuroshio and its extension, leading to a positive SST anomaly in the North Pacific. The atmospheric response to this SST anomaly involves a weakened Aleutian low, and the associated fluxes at the air-sea interface reinforce the initial SST anomaly, so that ocean and atmosphere act as a positive feedback system. The anomalous heat flux, reduced ocean mixing in response to a weakened storm track, and anomalous Ekman heat transport contribute to this positive feedback. The atmospheric response, however, consists also of a wind stress curl anomaly that spins down the subtropical ocean gyre, thereby reducing the poleward heat transport and the initial SST anomaly. The ocean adjusts with some time lag to the change in the wind stress curl, and it is this transient ocean response that allows continuous oscillations. The transient response can be expressed in terms of baroclinic planetary waves, and the decadal timescale of the oscillation is therefore determined to first order by wave timescales. Advection by the mean currents, however, is not negligible. The existence of such a cycle provides the basis of long-range climate forecasting over North America at decadal timescales. At a minimum, knowledge of the ... Article in Journal/Newspaper aleutian low Max Planck Society: MPG.PuRe Curl ENVELOPE(-63.071,-63.071,-70.797,-70.797) Pacific |
institution |
Open Polar |
collection |
Max Planck Society: MPG.PuRe |
op_collection_id |
ftpubman |
language |
English |
description |
The dynamics and predictability of decadal climate variability over the North Pacific and North America are investigated by analyzing various observational datasets and the output of a state of the art coupled ocean-atmosphere general circulation model that was integrated for 125 years. Both the observations and model results support the picture that the decadal variability in the region of interest is based on a cycle involving unstable ocean-atmosphere interactions over the North Pacific. The period of this cycle is of the order of a few decades. The cycle involves the two major circulation regimes in the North Pacific climate system, the subtropical ocean gyre, and the Aleutian low. When, for instance, the subtropical ocean gyre is anomalously strong, more warm tropical waters are transported poleward by the Kuroshio and its extension, leading to a positive SST anomaly in the North Pacific. The atmospheric response to this SST anomaly involves a weakened Aleutian low, and the associated fluxes at the air-sea interface reinforce the initial SST anomaly, so that ocean and atmosphere act as a positive feedback system. The anomalous heat flux, reduced ocean mixing in response to a weakened storm track, and anomalous Ekman heat transport contribute to this positive feedback. The atmospheric response, however, consists also of a wind stress curl anomaly that spins down the subtropical ocean gyre, thereby reducing the poleward heat transport and the initial SST anomaly. The ocean adjusts with some time lag to the change in the wind stress curl, and it is this transient ocean response that allows continuous oscillations. The transient response can be expressed in terms of baroclinic planetary waves, and the decadal timescale of the oscillation is therefore determined to first order by wave timescales. Advection by the mean currents, however, is not negligible. The existence of such a cycle provides the basis of long-range climate forecasting over North America at decadal timescales. At a minimum, knowledge of the ... |
format |
Article in Journal/Newspaper |
author |
Latif, M. Barnett, T. |
spellingShingle |
Latif, M. Barnett, T. Decadal climate variability over the North Pacific and North America: Dynamics and predictability |
author_facet |
Latif, M. Barnett, T. |
author_sort |
Latif, M. |
title |
Decadal climate variability over the North Pacific and North America: Dynamics and predictability |
title_short |
Decadal climate variability over the North Pacific and North America: Dynamics and predictability |
title_full |
Decadal climate variability over the North Pacific and North America: Dynamics and predictability |
title_fullStr |
Decadal climate variability over the North Pacific and North America: Dynamics and predictability |
title_full_unstemmed |
Decadal climate variability over the North Pacific and North America: Dynamics and predictability |
title_sort |
decadal climate variability over the north pacific and north america: dynamics and predictability |
publishDate |
1996 |
url |
http://hdl.handle.net/21.11116/0000-0003-2919-4 http://hdl.handle.net/21.11116/0000-0003-291B-2 http://hdl.handle.net/21.11116/0000-0003-291C-1 |
long_lat |
ENVELOPE(-63.071,-63.071,-70.797,-70.797) |
geographic |
Curl Pacific |
geographic_facet |
Curl Pacific |
genre |
aleutian low |
genre_facet |
aleutian low |
op_source |
Journal of Climate Report / Max-Planck-Institut für Meteorologie |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1175/1520-0442(1996)009<2407:DCVOTN>2.0.CO;2 http://hdl.handle.net/21.11116/0000-0003-2919-4 http://hdl.handle.net/21.11116/0000-0003-291B-2 http://hdl.handle.net/21.11116/0000-0003-291C-1 |
op_doi |
https://doi.org/10.1175/1520-0442(1996)009<2407:DCVOTN>2.0.CO;2 |
_version_ |
1774712885549727744 |